14 May 2020

CRISPR patent appeal dismissed

In one of the most eagerly awaited appeal proceedings in recent years, a European Patent Office (EPO) Board of Appeal (Board) has upheld the revocation of a patent relating to CRISPR/Cas9 technology.

As we reported previously, this case (T 0844/18) had potentially very significant implications for the European patent system because it concerned the requirements for validly claiming priority in Europe.

Had the appeal been successful it would have resulted in a significant change to current practice. The Board’s written decision, which will provide its detailed reasoning for arriving at its decision, has not yet been issued and is eagerly awaited.

In Europe, the right to claim priority is provided by Article 87(1) of the European Patent Convention (EPC), which states that “Any person who has duly filed … an application for a patent … or his successor in title, shall enjoy, for the purpose of filing a European patent application in respect of the same invention, a right of priority during a period of twelve months from the date of filing of the first application.”

Decades of EPO case law have established that the reference to “any person” in this provision is interpreted to mean that the applicant of a priority-claiming patent application must be the same person that filed the earlier application (or that person’s successor in title).

If the earlier application has joint applicants, the right to claim priority belongs jointly and indivisibly to all of the applicants, and priority can only be claimed from the earlier application if the priority-claiming application includes all of the joint applicants (or their successors in title).

Other countries, including the US, have less stringent priority requirements than the EPO. For example, in the US, the priority-claiming application requires just one joint applicant in common with the earlier application. The subject appeal proceedings revolved around and examined the stringency of the EPO’s requirements for claiming priority.

The subject European patent (EP2771468) was granted on 11 February 2015 to three co-proprietors, The Broad Institute, MIT and Harvard College. Grant of the patent by the EPO was opposed by nine separate parties.

The opponents of EP2771468 argued that the priority claims based on two US provisional applications were invalid, on the grounds that Luciano Marraffini of the Rockefeller University is listed as an applicant on the priority applications in question, but not on the priority-claiming Patent Corporation Treaty (PCT) application. No evidence was submitted to the EPO that Marraffini had assigned his rights to one of the applicants of the PCT application before that application was filed.

In its decision, the EPO held that the right to claim priority had not been properly assigned and, therefore, the priority claim was invalid. As a result of this finding, the claimed subject matter was found to lack novelty over a number of documents which became relevant as prior art due to the loss of the patent’s priority date.

The patent proprietors appealed the EPO’s decision to revoke the patent. Three main arguments were presented in support of the appeal. The first argument was that priority entitlement should not be examined by the EPO but should instead be a matter for national courts to determine. The second argument was that the reference to “any person” in Article 87(1) EPC should be interpreted to mean “at least one”, rather than “all” of the joint applicants. Finally, it was argued that national law of the state in which the priority application was filed should determine who qualifies as “any person” in Article 87(1) EPC.

In the preliminary opinion issued by the Board in preparation for the appeal hearing, the Board indicated that the case appears to turn on the pros and cons of altering the EPO’s practice concerning the interpretation of the reference to “any person” in Article 87(1) EPC in the case of joint applicants for the priority application. Factors for maintaining the present practice were said to include the fact that the practice is long-standing, it protects joint applicants against the actions of other joint applicants and any problems can be avoided using sufficient foresight. As a consideration in favour of changing the current practice, the Board acknowledged that relaxing the required formalities may be more in line with the aim of the Paris Convention.

During the appeal hearing it briefly appeared that the Board was moving to refer questions on priority entitlement to the Enlarged Board of Appeal (Enlarged Board), the EPO’s highest decision-making body. However, the Board ultimately elected to decide on this point of law without a referral to the Enlarged Board.

After a hearing lasting four days, the Board dismissed the appeal, finding that the priority claim was invalid, meaning that the Opposition Division’s findings in relation to novelty were upheld.

Had the Board overturned the original decision it would have marked a radical departure from decades of jurisprudence on a fundamental concept in European patent law. For this reason at least, the Board’s decision was perhaps not entirely unexpected.

Since the decision upholds the EPO’s current requirements and well established case law, applicants will not need to change their current practice in light of the decision. Nevertheless, this case serves as an important reminder that all applicants of a priority application (or their successors in title) must be listed on the priority-claiming application, and failure to observe the EPO’s requirements for priority can have fatal consequences for the patent.